Carbon Storage And Influence Factors Of Major Mangrove Communities In Fucheng,Leizhou Peninsula,Guangdong Province

Mangrove ecosystem occupies high carbon storage and strong carbon sequestration potential.It maximized the carbon storage if suitable mangrove species and the best environment would be chosen to improve the forest stand and afforest.Selecting mangrove which was at Fucheng town of Leizhou peninsula,Guangdong province as the research object,we compared with carbon storage of different age,sea level,tree species and plant model,optimized vertical structure and afforested carbon sequestration forest at mudflats which have characteristics of high salinity,long time tide-flooding and sandy soil.In this study,carbon stocks include two parts,the vegetation and soil carbon stocks.Vegetation carbon stocks were quantified by measuring the biomass of trunk,root and downed woody debris.Soil organic carbon was measured to quantify soil carbon stocks.The results showed that(1)Carbon storage of mangrove communities was raised by the increase of age of which major reason was the increase of soil carbon storage.The period at the hightest rate of carbon storage of Sonneratia apetala and Kandelia obovata was 1-5 year and 1-20 year.(2)Carbon stocks of mangrove which were at high tide level was higher than those which were at low tide level.Influence of tidal and tree factors on carbon storage had interaction effect.Tidal factors had different influence on different tree.(3)Carbon storage of 20-year old communities was ranked that Sonneratia apetalaAegiceras corniculatum> Aegiceras corniculatum+ Kandelia obovata> Sonneratia apetala> Aegiceras corniculatum> Sonneratia apetala-Avicennia marina> Kandelia obovata> Avicennia marin,which value was separately 305.52?236.26?178.15?172.96?145.99?136.98?97.42t·hm-1.(4)After 30 months in which vertical structure had been optimized,carbon density of S.apetala which was planted A.corniculatum and A.marina compared with non-optimized S.apetala increased by 38.07 and 16.69 t·hm-2 and the increase rate was 60.62% and 26.58%.The rate of carbon storage added to 17.96 ? 4.8 t·hm-2·a-1.Survival rate of A.marina maintained over 80% while A.corniculatum declined to 30%.Based on the sustainablecarbon sequestration,A.marina was chosen as indigenous tree species to optimize vertical structure of carbon sequestration forest.(5)When carbon sequestration forest was constructed,the carbon density of L.racemosa-A.corniculatum,S.apetala,L.racemosa,S.apetala-A.marina was up to 45 t·hm-2.In the low tidal zone,the carbon sequestration of all sample plots except A.marina decreased by over 30% so that tidal zone had an obvious influence on carbon sequestration.Survival rate of L.racemosa and A.corniculatum was under 40% while other species sustained over 70%.According to survival rate and carbon sequestration,S.apetala and S.apetala-A.marina were chosen to afforest at the high tidal zone as there was strong carbon sequestration and excellent environment adaptation.A.marina and K.obovata were chosen to afforest at the low tidal zone as they adapted to habitat of low tidal zone and the decline of carbon sequestration was smaller with the decrease of tidal zone.(6)Soil bulk density increased with the increase of depth,while the TOC content decreased.Soil layer of the hightest soil density was 0-20 cm or 20-40 cm.